Decorative elements comprising a rigid or flexible substrate optionally having on the front surface a 3-dimensional design which is covered with a transparent plastic material, are described in literature.
U.S. Pat. No. 4,356,617 describes a decorative emblem using a metal foil as a substrate bearing indicia applied by silk screen or lithographic printing. The metal foil may subsequently be embossed to provide a 3-dimensional design. Then a fluent, viscous plastic material such as a polyurethane is cast onto the optionally embossed indicia which melds together and forms a meniscus which, when hardened, gives a lens effect to the resulting decorative emblem. In order to control the flow of fluent plastic and meniscus formation, a sharply defined peripheral edge such as a dike is formed, for example, during the embossing step or is printed onto the metal foil. The decorative emblem may comprise a layer of a pressure-sensitive adhesive on the back surface of the metal foil to allow for adhering it to the intended surface. The fluent, viscous plastic material may be selected from heat-curable materials such as polyurethanes. Radiation curable materials are, described, for example, in U.S. Pat. No. 4,087,570 or U.S. 4,259,388. U.S. 4,566,929 describes a flexible trim strip suitable for application to an automobile body comprising an elongate molding with a longitudinal channel, a decorative surface in said channel and a weather-resistant and impact-resistant plastic overlay having radiused edges which provide a lens effect to the decorative surface beneath.
U.S. Pat. No. 4,767,674 and U.S. 4,481,160 describe decorative emblems using a bezel having a cavity formed by a generally flat base and vertically upstanding peripheral sidewalls or dikes as a substrate which may be formed of a plastic such as an acrylonitrile-butadiene-styrene (ABS) resin. Subsequently to an initial casting of a fluent plastic material into the cavity, a decorative foil is placed therein and subjected to a second casting of fluent plastic material to form a lens cap over the foil and completely encapsulating it in plastic. The decorative foil may be a metal foil which is brushed, printed, optionally embossed and die-cut to fit into the cavity. The bezel may comprise an adhesive layer on the back surface to attach the resulting decorative emblem to the intended surface.
The decorative ornament described in JP 61-249,758 is obtained by first providing a substrate having protruded parts via injection molding of, for example, polyvinyl chloride or ABS. Then a pigmented polyurethane resin is poured over the protruded parts and cured followed by the application of a curable, transparent synthetic resin that has a meniscus.
U.S. Pat. No. 4,330,578 describes a process for preparing a synthetic resin decorative article comprising first forming a molded piece by injection molding which preferably has a flat surface onto which a designed pattern is printed. The molded piece is then placed into a second mold to form a synthetic resin decorative article consisting essentially of two injection molded, superimposed thermoplastic resin bodies and at least one integral layer of a cured thermosetting ink enclosed within the molded bodies.
U.S. Pat. No. 4,427,615 describes a method for preparing injection molded plastic objects. In this method a foil is inserted into the mold cavity so that the foil is pressed into engagement with the button and/or top of the mold cavity by molding material injected under pressure.
The decorative elements which are available so far, do not fulfill all aesthetic requirements to a desired degree and/or the method of their production can be complicated or expensive. Therefore there has been a need for providing decorative elements which are highly appealing from an aesthetic point of view and a technically and economically acceptable method of preparing them.